The government is considering 'COVID certificates' as a way of letting people attend larger events, culture secretary Oliver Dowden has said.
The idea would allow people to return to major events "in significant numbers" as part of a cautious return to normality following the COVID pandemic.
Dowden said ministers are reviewing the possibility of introducing a document providing proof that a person has either received a COVID vaccine or tested negative for the virus.
Under the government’s current roadmap for easing restrictions, crowds of up to 10,000 in the largest venues could be allowed at performances and sporting events from 17 May.
It is hoped that all remaining restrictions on larger events and performances could be lifted from 21 June, which is the earliest date for all legal limits on social contact to be removed.
The organisers of Glastonbury festival, which has been cancelled for the second year running, have put in an application to stage a one-off event in September, the Guardian reported.
Watch: Fans could be back in 'significant numbers' this summer with COVID certificates
Speaking to Sky News, Dowden said: "From June 21, if all goes to plan in the way that I described, we hope to get people back in significant numbers.
"We're piloting the different things that will enable that to happen – clearly it will have to be done in a COVID-secure way."
He added: "You would expect, and we will be testing these things, things like one-way systems, things like masks, things like hand hygiene and everything else.
"Another thing that we are considering is a COVID certification, and we will be testing whether we can use COVID certification to help facilitate the return of sports."
What are COVID certificates?
The COVID certificates the government is talking about are essentially documents that provide proof that someone has either received a COVID vaccine or has tested negative for the virus.
That way, the hope is that they would allow larger numbers of people to gather at events such as concerts or sporting events without the risk of spreading the virus.
The events that could ask for a COVID certificate
It's likely that COVID certificates would be used at major sporting events that attract large crowds.
The FA Cup Final and the World Snooker Championship are among pilot events designed to test the large-scale return of spectators to venues, as the country seeks to reopen following the latest coronavirus lockdown.
The FA Cup final at Wembley Stadium is going to be used as a test for the return of larger audiences at sporting events, theatres and gigs.
It is not yet know how many people will be allowed to go but Sky Sports News reported that the government was in talks over the potential of up to 20,000 fans attending the match - far beyond the 10,000 limit for larger outdoor seated venues that is due to come into force from 17 May.
This week the Cheltenham Festival took place without the vast crowds who usually attend the biggest racing event of the year.
The government was criticised for allowed the event to go ahead last year as the pandemic was just starting.
What other measures will there be?
Dowden said everything will have to be done in a COVID-secure way to allow events to continue.
Some measures the government will be testing include: one-way systems, wearing masks, hand washing and sanitising.
He also suggested that social distancing measures could potentially remain in place, with current guidelines making it “very, very difficult” for indoor events such as theatre productions to go ahead.
“I hope we will be able to find ways of mitigating against, certainly, having the sort of social distancing that we have at the moment,” he told Sky News.
He added: “The sort of social distancing we have at the moment makes it very, very difficult, for example, for theatre productions to be run profitably.
“It makes it very, very difficult for our football clubs to run profitably if you have to have those large distances between people.
“Clearly, we have been in the situation for the past year where we have had to have those distances, so we are proceeding with caution, that’s why it’s the last stage, that’s why we are piloting different ways of mitigating against that.”
Are COVID certificates the same as a vaccine passport and can they be used for travel?
It's not yet clear, but the discussion around COVID certificates is related to helping a return to major events rather than travel.
International travel is slated to restart on 17 May, with the government due to assess this on 12 April.
Several countries are exploring the idea of vaccine passports, with countries like Greece and the Seychelles already saying they will welcome travellers who can provide proof that they have been vaccinated, while Turkey has announced earlier this week they would let travellers in without proof of vaccination.
The EU has also proposed a vaccine passport system to allow its citizens to travel around Europe.
However, it's unlikely that the COVID certificates that the government is talking about will be the same thing.
Watch: How England will leave lockdown